Procollagen type 1 N propeptide (P1NP)

Also known as procollagen extension peptide. Procollagen 1 (P1NP) concentrations reflect osteoblast activity so any disease increasing the activity of osteoblasts or activation frequency of the bone forming unit will result in elevated P1NP concentrations. Low P1NP may indicate adynamic bone. This test is currently only available to the Endocrinologists / bone clinic for monitoring response to anti-resorption therapy. P1NP shows minimal circadian rhythm or seasonal variation. Food intake or diet show no detectable influence on plasma levels. A baseline pre-treatment measurement is required if assessing response to antiresorption therapy.